When you hear the phrase "happy foods," which dishes come to mind? Many people think of sugary desserts or fatty fast foods, says Felice Jacka with the Food and Mood Centre at Deakin University, in Geelong, Australia. After all, in the U.S., we celebrate with cake and ice cream. Parties often feature pizza. Our Thanksgiving feasts usually end in an array of pies and whipped cream.
But the idea that these foods will make you happy comes directly from advertisers, Jacka says. "People are like walking wallets to food companies," and they sell you this myth that eating these foods will make you feel good.
"It's a bit like if you gave someone a glass of champagne. Feels good in the short term, but the long-term impact is the opposite," Jacka says.
Food impacts mood
For the past fifteen years, Jacka and her colleagues have pioneered the field of nutritional psychiatry. They study how various foods affect people's moods and mental health. And they've found some foods are uplifting and protect us from depression. While others sour our mood and increase our risk of depression.
There's mounting evidence that sweets and ultra-processed foods fall squarely in the second category.
Studies have found that people can feel anxious, irritable, angry or lethargic several hours after eating foods packed in refined carbohydrates and sugars. "For example, some weekend mornings, I go to a diner and have a waffle. By 10 o'clock, I feel terrible," says pediatric gastroenterologist Dr. Kara Margolis at New York University, who studies how gut health connects to mood disorders.
And over the long-run — say months and years — too many of these foods may affect your mental health. Large epidemiological studies across several cultures have shown that a diet high in ultra-processed foods and refined carbohydrates raises a person's risk for depression. "We can see that it's associated with a 20 to 30 percent higher risk," Margolis says.
At the same time, several randomized control studies have found that when people remove ultra-processed foods from their diet and replace them with more whole and minimally processed foods, their depression decreases.
Here's the conundrum: when people believe these ultra-processed foods make them happier, studies have found, people tend to eat more of them.
Happy microbes, happy people?
So if ice cream, cake and processed French fries aren't the happiest foods out there, what are? Scientists are still trying to nail down that answer. But the doctors and scientists interviewed for this story all pointed to one top candidate: "Whole grains seem to be particularly important," Jacka says.
Whole grains contain a special type of fiber, called fermentable fiber, which bacteria in your gut can digest. It improves the health of your microbiome, Margolis explains, by feeding the "good versus bad bacteria." When the microbes eat this fiber, they produce small molecules that are linked to a whole host of benefits, including decreased inflammation, improved insulin sensitivity, and better communication between the gut and the brain. All of these effects have been associated with improved mood and a decreased risk of mood disorders, Margolis says.
"Making the environment in your gut right for good bacteria not only can affect mood, but it can protect you from nearly every medical condition that's been studied," she adds, including heart disease and diabetes.
So if you are looking to boost your holiday mood, here are a few things to try.
1. Go home made
There are two fundamental ways you can influence your mood with your diet, says Felice Jacka at Deakin University. "They're both quite independent of each other."
First off, she says, you can cut back on ultra-processed foods. That includes foods with added preservatives, artificial sweeteners, refined carbohydrates and white flours, natural and artificial flavors, and emulsifiers, such as soy lecithin, xanthan gum and guar gum.
Over Thanksgiving, skip the store-bought pastries, pies, crackers, and white breads. Avoid fast-food pizzas and burgers. Try making your favorite foods in your kitchen with traditional ingredients, Jacka says. "For example, make a beautiful, flour-free cake using almond meal and honey. It's still going to be sweet, but it's going to be a heck of a lot better for your mood, than what you'll find in the supermarket.
2. Don't make the holidays white
The second way to boost your mood with your diet, Jacka says, is increase your consumption of whole grains.
Instead of grabbing a croissant or sugary cereal for breakfast, have a bowl of overnight oats or a savory congee (made with brown rice). Toss corn or barley into your salads. Eat corn tortillas instead of flour ones. Swap out biscuits and dinner rolls for 100% whole wheat breads or pastas.
When you're baking pies, cookies, and cakes, you can substitute the white flour in the recipe for whole grain flours, such oat, barley, or whole wheat. Same goes with pizza: have the kids create a 100% whole wheat pizza from scratch this holiday. Or make whole wheat bread in a bread machine.
3. Beef up on beans & lentils
There's another major way to eat this mood-boosting fiber, says Dr. Meroë Morse at The University of Texas MD Anderson Cancer Center: Eat beans and lentils. "Your microbiome loves beans," she says.
"In our research, we see that a very small amount of beans in your diet can actually greatly impact your microbiome in a good way," Morse says. Unlike many leafy greens or many vegetables, you don't have to eat many beans to get a hefty dose of fiber. For example, a quarter cup of cooked black beans contains about five to seven grams of fiber.
Dried beans and lentils are also a super inexpensive way to boost fiber, says Hannah Holscher, who's a microbiome scientist and dietitian at the University of Illinois Urbana-Champaign. "Now that we're getting into soup season, just pick your favorite soup, pick your favorite bean and add them into the soup."
Dried lentils cook up quickly because they don't need soaking. "We frequently eat lentils in our house," she says. "You can saute some onions with tomatoes and olive oil. Then add lentils with different Indian spices," she says. "It's delicious." Or make a big pot of Thanksgiving chili with both beans and lentils.
4. Take it slowly
Keep in mind, beans, lentils, and dense whole grains are powerful foods for your gut, Holsher says. Start off with a small serving and titrate up slowly over time.
With beans, some individuals will get a bit of gas and bloating if they eat too many or they're not used to eating them. "Try a few different varieties," Holscher recommends. "Or soak the beans beforehand. That can help to reduce any types of unwanted side effects."
You can also find high amounts of fermentable fiber in chia seeds, berries, apples, pears, avocados and unripe bananas.
After your microbiome adjusts, the bacteria will thank you by raising up your mood long-term. After all, studies suggest that when your gut bacteria are happy — they make you happy as well.
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